Catecholamines are compounds which possess a catechol nucleus - a benzene ring with two adjacent hydroxyl groups - and an amine containing side chain. They include isoprenaline, dopamine, dobutamine, adrenalin, noradrenalin, and dopexamine. Catecholamines act on the beta receptor; specifically acting on the G protein, resulting in the production of more cAMP, which has an effect on phosphate kinase.

A summary of their actions is as follows:

alpha beta1 beta2 dopaminergic

isoprenaline + + dopamine + (high) + + (low) dobutamine + +(minor) adrenaline + + + dopexamine + +